<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css">
		.box,.box1{
			width: 200px;
			height: 200px;
			border: 1px solid red;
			float: left;
		}
		.box1{
			border:1px solid green;
			margin-left:-1px;
		}

	</style>
</head>
<body>
	<div class="box"></div>
	<div class="box1"></div>
	

	
</body>
</html>